Re: Write Signal on Disk II Question

I have done a lot of timing-critical stuff over the parallel port. It
works very well, if you
- run a single-task operating system (Plain DOS)
- make use of the CLI instruction while doing critical timing
- access the parallel port in every timing loop (this keeps the ISA-
bus loaded all the time and gives quite accurate delays)
- make all timing-critical code and data fit inside the L1-cache.

The timing I yielded with it was VERY stable, so I don't see the
problem here. I think the problem is not to miss any pulse and to find
out when to stop.
I would like to read a whole track and decode it then, but how do I
find out when the track is finished...?
I want to keep the logic in the timing-critical part as simple as
possible. Maybe it's best read for at least 2 revolutions and to hopt
that the sectors are somewhere in the track.
I will think of it...

.

Relevant Pages

  • Re: Serial-based OS: crazy idea?
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  • Re: Timing in Synch Comm.
    ... because its pre-emptive there can be extreme latency in the timing. ... will be some of the protocols I'll try and implement. ... Eventually I might add support for usb and some other devices but at this point all I have is the parallel port. ...
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  • Re: Timing in Synch Comm.
    ... because its pre-emptive there can be extreme latency in the timing. ... will be some of the protocols I'll try and implement. ... There is no point in developing anything for the parallel port now. ...
    (sci.electronics.design)
  • Re: Timing in Synch Comm.
    ... timing. ... and ICSP will be some of the protocols I'll try and implement. ... There is no point in developing anything for the parallel port now. ... I would not bet on that either, while USB ip is cheap ethernet ip is ...
    (sci.electronics.design)
  • Re: Timing in Synch Comm.
    ... Joerg wrote: ... because its pre-emptive there can be extreme latency in the timing. ... What else is the PC parallel port can be used for if not for the simulation of the SPI or I2C by bit banging? ...
    (sci.electronics.design)